According to a September 8 USA Today/Gallup poll, the Republican National Convention gave the McCain–Palin ticket “a ‘rebound’ bounce,” and a “slight edge” over the Democratic candidates. Prior to the Democrats’ convention, a USA Today/Gallup poll found the presidential race at a dead heat—45 percent. But the DNC gave Ill. Sen. Barack Obama a lead of 47 percent to Ariz. Sen. John McCain’s 43, and Sen. Obama was as high as 50 percent in the days prior to the RNC. Now Sen. McCain has reversed that, leading Obama 50 percent to 46.

A poll by SurveyUSA, also released September 8, suggests a five-point lead for McCain among participants asked to “bet on” the winner of the election: 49 percent said McCain to Obama’s 44 percent.

A Rasmussen daily tracking poll from September 8 counters the above polls, showing only a “statistically insignificant one-point lead” for McCain over Obama. But other Rasmussen data is more encouraging for McCain: “Overall, McCain is now viewed favorably by 60% of the nation’s voters,” Rasmussen writes, “while Obama earns positive reviews from 55%.” Further, the Republican Convention “appears to have created a larger surge in party identification than the Democratic convention the week before.”

The media will play an even bigger role in the polls in the coming weeks, as Alaska Gov. Sarah Palin sits down with ABC this week for her first interview as vice-presidential nominee, and as the presidential candidates prepare for their first debate September 26. Though some are questioning the value of such an interview, Steven Benen of The Washington Monthly blog Political Animal says “she’ll be fine,” helped by the fact that the interview is being held in Alaska and she will have had about a week to prepare for the appearance.

Historically speaking, the Democratic and Republican national conventions typically lead to a boost in the respective party’s national approval rating. The atmosphere following this year’s RNC is similar to what followed President George H.W. Bush’s nomination at the 1988 convention. Though approval for his vice-presidential nominee Dan Quayle was at a historic low prior to the convention—just a few points lower than Gov. Palin’s national approval rating was found to be by an August 29 Gallup poll—Bush left the convention with a lead and went on to win the election.

Out of “likely voter” numbers, the latest USA/Gallup poll shows that McCain has a 10-point lead over Obama and a four-point lead among registered voters, but Nate Silver of the polling site FiveThirtyEight believes that the larger gain is not “especially credible, as the Gallup likely voter model is infamous for overstating the effects of short-term shifts in enthusiasm.” Still, Silver agrees this is a “pretty decent-sized bounce” for the Republican candidate.

Silver’s analysis of the latest numbers takes into account what he calls the “Shy Tory Factor,” used to describe Tory voters in the British elections in the 1990s who were said to be underrepresented in polls, “perhaps owing to response bias.” Silver attributes the McCain boost to Palin, whom many say has given “a jolt of energy” among “shy” Republican voters, if this group exists.

NBC’s political director Chuck Todd discussed the recent polls on “The Today Show” September 8, remarking that the Gallup poll is “erratic” and has qualities in common with an “EKG monitor” for the heart because it polls so frequently. But Todd believes that Palin is responsible for closing the “enthusiasm gap” prior to and during the RNC and could be helping to convert “soft Republican women” on the fence and help to “gel” the Republicans in states like Missouri.

Ed Morrissey of the blog Hot Air puts more value on the 10-point lead Gallup found among likely voters, saying that McCain “appears to have broken through to new voters rather than just reshuffle the deck. … Republican enthusiasm numbers have shot upward sharply, almost matching those of the Democrats,” and again, Morissey says this is primarily Palin’s doing.

Whether McCain’s lead will last has a lot to do with the candidates’ performances in interviews and debates. Anticipation of Palin’s first interview and debates with the Democratic candidate for vice president, Del. Sen. Joe Biden. is mounting as the events fill the gap left by the convention. Steve Benen of the Washington Monthly’s Political Animal blog says of Palin’s impending ABC interview: “A couple of weeks of intensive prepping for a capable politician, coupled with an ability to dodge and filibuster, all on her home'"turf,'"—the interview will see ABC anchor Charles Gibson traveling to Alaska—“should be more than enough to get through the interview without any trouble at all.”

Josh Marshall of Talking Points Memo says that the McCain campaign has been particularly protective of Palin, and suggests that the ABC interview is pandering to their requests, making things easier on Palin by dividing the interview into segments. “The interviewer has to be on their best behavior, at least until the last of the ‘multiple interviews’ because otherwise the subsequent sittings just won't happen,” Marshall says. But this approach was used by the Obama campaign during the Bill O’Reilly interview with Obama last week; it was divided into four parts.